My experience has been different. I use the Rio FF almost exclusively myself. I do a lot of fishing where abrasion resistance from jagged rocks and turbulence is very important. And I need to goto 2X, sometimes 3X, for the steelies I target. Since I'm referring to a situation where I'm bottom drifting a two fly tandem, and almost never break off at the knot tied to the hook bend of the upper fly, I'm pretty sure abrasion is the main culprit for break offs. At first I used the original Rio FF and soon noticed I had to check tippet to eye knots frequently as they were losing strength presumably from the bottom rock abrasion. Mono was never an option due to the lower visibility of FF. But a few I know, and who are very knowledgeable fishermen, still prefer Maxima tippet citing the better abrasion resistance. Later FF+ came out and I was elated to read of the greater break strength and thought this would be the answer to the abrasion problems. Not to be. I got more suspicious break offs with this material than with the original FF. I concluded it to be less reliable than the original FF where abrasion is concerned. I am now back to using the original FF

One aspect that really gives me fits is that I have a use where I need to tie 3X directly to 1X. Now the surgeons knot would seem to be the answer. But when I first tie and test this knot it usually breaks. On repeating the tie a second and sometimes a third time, I can finally get it to pass the break test. Its as if the tippet has to be broken in to the tying process!!?? Once I get a knot to pass the test it is usually very reliable. I was using a double surgeons to start with here but recently went to a triple surgeons and while the jury is still out, this extra turn does seem to improve my result but not all the time.